Secure transfer and tracking of data using removable nonvolatile memory devices

Abstract

A protected memory source device including removable non-volatile memory durably stores a signature such as a serial number or identifier, which is used to mark protected multimedia content legally stored on the protected memory device. The protected multimedia content is moved from the source device to another device, such as a target device used to aggregated protected content in a library. Moving the protected multimedia content involves replacing a source-specific header, comprising digital rights management metadata and/or other security metadata allowing only a device having the source device signature access to the content, with a target-specific header comprising digital rights management metadata and/or other security metadata allowing only a device having the target device signature access to the content. The transfer is done using one of a variety of transfer methods with either a trusted or un-trusted host system connecting the source device to the target device.

We claim: 
     
       1. A computer-implemented method of transferring content, performed on a source device having one or more processors and memory storing one or more programs which when executed by the one or more processors cause performance of the method, the method comprising:
 receiving from a target device, a target device signature; 
 accessing a content file having encrypted content and a source-specific header allowing only a device having a source device signature access to the encrypted content, wherein the source device comprises a removable device having non-volatile semiconductor memory storing one or more content files; 
 decrypting the encrypted content using a content key; 
 removing source-specific information from the content; 
 adding target-specific information to the content, wherein the source-specific information is one or more of a source watermark and source stenographic information; wherein the target-specific information is one or more of a target watermark and target stenographic information; wherein the source watermark and the source stenographic information include information unique only to the source; and wherein the target watermark and the target stenographic information include information unique only to the target; 
 creating a new content key; 
 encrypting the decrypted content with the new content key to create re-encrypted content; 
 creating for the content file a target-specific header allowing only a device having the target device signature access to the content; 
 encrypting the target-specific header; then 
 transferring to the target device, the content file with the re-encrypted content, the new content key and the encrypted target-specific header. 
 
     
     
       2. The computer-implemented method of  claim 1  wherein the target specific header is created by using a target device signature to convert an intermediate header into the target specific header. 
     
     
       3. A computer-implemented method of transferring content, performed on a source device having one or more processors and memory storing one or more programs which when executed by the one or more processors cause performance of the method, the method comprising:
 accessing a content file having encrypted content and a source-specific header allowing only a device having a source device signature access to the encrypted content, wherein the source device comprises a removable device having non-volatile semiconductor memory storing one or more content files, wherein the source device signature is a serial number of the source device, is a value that is a predefined function of the serial number of the source device, or is a set of alpha-numeric characters that identify the source device; 
 removing source-specific information from the content; 
 adding target-specific information to the content, wherein the source-specific information is one or more of a source watermark and source stenographic information, wherein the target-specific information is one or more of a target watermark and target stenographic information, wherein the source watermark and the source stenographic information include information unique only to the source, and wherein the target watermark and the target stenographic information include information unique only to the target; 
 creating for the content file a target-specific header allowing only a device having the target device signature access to the content; 
 encrypting the target-specific header; then 
 transferring to the target device, the content file with the re-encrypted content and the encrypted target-specific header. 
 
     
     
       4. The computer-implemented method of  claim 3  wherein the target specific header is created by using a target device signature to convert an intermediate header into the target specific header. 
     
     
       5. A source device comprising:
 one or more processors and memory storing one or more programs which when executed by the one or more processors cause:
 receiving from a target device, a target device signature; 
 accessing a content file having encrypted content and a source-specific header allowing only a device having a source device signature access to the encrypted content, wherein the source device comprises a removable device having non-volatile semiconductor memory storing one or more content files; 
 decrypting the encrypted content using a content key; 
 removing source-specific information from the content; 
 adding target-specific information to the content, wherein the source-specific information is one or more of a source watermark and source stenographic information; wherein the target-specific information is one or more of a target watermark and target stenographic information; wherein the source watermark and the source stenographic information include information unique only to the source; and wherein the target watermark and the target stenographic information include information unique only to the target; 
 creating a new content key; 
 encrypting the decrypted content with the new content key to create re-encrypted content; 
 creating for the content file a target-specific header allowing only a device having the target device signature access to the content; 
 encrypting the target-specific header; then 
 transferring to the target device, the content file with the re-encrypted content, the new content key and the encrypted target-specific header. 
 
 
     
     
       6. The source device of  claim 5  wherein the source device comprises a physical interface for removably interconnecting or a wireless interface for communicating with a host device. 
     
     
       7. A source device comprising:
 one or more processors and memory storing one or more programs which when executed by the one or more processors cause:
 accessing a content file having encrypted content and a source-specific header allowing only a device having a source device signature access to the encrypted content, wherein the source device comprises a removable device having non-volatile semiconductor memory storing one or more content files, wherein the source device signature is a serial number of the source device, is a value that is a predefined function of the serial number of the source device, or is a set of alpha-numeric characters that identify the source device; 
 removing source-specific information from the content; 
 adding target-specific information to the content, wherein the source-specific information is one or more of a source watermark and source stenographic information, wherein the target-specific information is one or more of a target watermark and target stenographic information, wherein the source watermark and the source stenographic information include information unique only to the source, and wherein the target watermark and the target stenographic information include information unique only to the target; 
 creating for the content file a target-specific header allowing only a device having the target device signature access to the content; 
 encrypting the target-specific header; then 
 transferring to the target device, the content file with the re-encrypted content and the encrypted target-specific header. 
 
 
     
     
       8. The source device of  claim 7  wherein the target specific header is created by using a target device signature to convert an intermediate header into the target specific header.